core: add getFileNameWithExtension utility

packages/core/utils/filename.ts

@@ -0,0 +1,40 @@
+/*
+This file is part of the Notesnook project (https://notesnook.com/)
+
+Copyright (C) 2023 Streetwriters (Private) Limited
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+type MimeTypeInfo = {
+  source: string;
+  extensions?: string[];
+  charset?: string;
+  compressible?: boolean;
+};
+
+let db: Record<string, MimeTypeInfo>;
+export function getFileNameWithExtension(filename: string, mime?: string) {
+  if (!mime || mime === "application/octet-stream") return filename;
+  if (!db) db = require("mime-db");
+  const mimeData = db[mime];
+  if (!mimeData || !mimeData.extensions || mimeData.extensions.length === 0)
+    return filename;
+  const extension = mimeData.extensions[0];
+
+  if (mimeData.extensions.some((extension) => filename.endsWith(extension)))
+    return filename;
+
+  return `${filename}.${extension}`;
+}